Telegraph repeater



'June 13, 1933. R. B. HEARN 1,913,443

TELEGRAPH REPEATER Filed Feb. 10, 1932 |||l|| FIG. I E54 1 3 AT TORNEV Patented June 13, 1933 nfinns itn; or psoqxr mw yorixinssienon am; TEIEPHQNE L ABQs is RA'IORIES, moonronarnnfiornnw YORK, 1v. YE, LAfQQRIQRATIo w K in PATENT OFFICE-*4 i TELEGRAPH REPEATER' This invention relates to repeatercircuits for use in: coinlnun catlon systems and more particularly to telegraph repeater circuitsQ An object of this invention is to improve and to increase the efliciency and the speed of operation of telegraph repeater circuits.

i l featureof this invention residesin the;

novel circuitretarding means provided for! insuring the proper operation (of the polar, relays of i order.

the repeater in a predetermined 1 fAno ther feature the polar relay biasing arrangement provided for effecting repeater ,operation.

telegraph repeater circuitsi e 'n 'iloy ngpolar Y It is Well known in art that single line relays havebeen usedi' or repeating signals in telegraph communicating systems. He

peater circuits of this type are disclosed in U. S. Patents 1,479A80, to J M. Fell January 1, 1924 andl,752,436,to F. S. Kinkead,

I April 1, 1930. H I-leretofore thespeeclof operation ofthe repeater circuits has beenliinited a to a degree at least by the ability of the re peaterrelays to operate quicklyiand in a predetermined order." Thisliinitation on'tlie speed] of operation has been successfully overcome by the circuit scheme designed in prlnciples underly ng comprises a four line telegraphsystein which is capable of repeating signals lnoreefiiciently and at higher speeds thankheretoforei Electrical retarding means are employed in this arrangement i which comprise a plurality condensers connected to one or more neutral relays for;

a rotary; 1

a holding the polarized relays in the operated 1 position for a slight-interval o t ti ne dur it ing the signalingintervals until other circuit arrangements seize control of the polar relays. The operation of this repeater except, i for the condenserfholding circuit is similarg toian extent at least, to the operation of the usual four polar relay single linerepeatersm A modified form of this inventiona'utilizes t Fig. 3 shows arotary selector replacing neutral relays. i

contacts of tion 1 5 a1 vvhioh actuates the. as soc'iatecl v receiving a a-p 1) station 2 Iflovlving sel cwri s heme 1 ton r pl cing we eu r llmlding re ay-t i 1 Telameness may! 1 were final y 1 un er?- stood fron fore [following description gether ivitli the accompanying drawing which illustrates one form of e nbodiinent'oi T theinvention. Itlis tol understood, how -v ever-grim this description is noti torestrict or limit the scope of this invention as defined in the appended claims, J

, Eigll illustrates asimplerernhodirnent of 1 theinvention employing fourpolar re ays; two being the line relays LW and'LE andioo the remaining two beingvauxiliary relays l i and AE; Two neutral relays SWQand SE areeinployedfor switching purposesff F 2 shows a modification employing only one neutral relayIS having a large umher of springs for switching purposes.

.fl FOl purposes of explanation letitlie same that station 1 is transmitting signals 1 my hr ugh r pe t rfi t ta i n i transmitting device 35 Sta op'ene kth lin c ents nte n -l a PM :me mpt b jQ th J i e s nk a ruptedf I i i rent in the line windings 4, and 7 1 of, rela s; All? and respectivelyy'allows the eurrent flowinginwindings 5 and 8, respectively, to operate theserelays to their spaeingposit ons; I

In the spacing position the lANVl relay closes a I holding circuit for the AE relay froniibattery' throughjits contact, Winding 13 of the l AE relay to 1 g oun ems tending to hold a h AE lay Op r -i A 9, theLW re ay interrupts L the line enl r er from station paratus', such asfrelayw39, andsoundenAOL; Since the current in ivin'ding of E tendsto hold thislrejlay in the nia tion,the interruption theilllile lQll ll relay w l ne rs ens :1 e aclq dil 10118 reme i d i r e l iwith the wind iis 1 s yA ,t r behtectsQ t we r rd-t e r ist-i91 of new A A i i i 1 u r n -i i W ding 3Wil fh time to: w th the value required to hold relayi l in the me kie ms t $1 th ti h v lam o, will i a ot be ecte ibyflthq eQli refine ents 3e t one; Then when;thejtransn itting;

n M w M, it 1 r se as at sta ess messes lemmas, heir A end of the signal impulse, current over the associated transmission line will start to flow in windings 4 and 7 of relays AW and LW', respectively. Since this line current opposes and overcomes the effect of the current in windings 5 and 8, respectively of these relays, they are operated to their'marking position where the LWV relay recloses the line circuit to station 2 and thereby actuates the associated receiving squipment' such as relay 39 and sounder 4.0. 7 Relay ATV in moving to the marking position interrupts the holding current for relay AE. Condenser 22, however, is provided: throughcontacts of relay SW in parallel with winding 13 of relay AE to retard this relay so the line current through the line winding 11 may have time to reach the value required to hold this relay in the marking position. Thus signal impulses from stationl are repeated to station 2.

Should. station 2 desire to interrupt the signals from station'l, the transmitting device 38 at station 2 is actuated opening the line circuit. If the line is already open at station 1, this will have no effect until the line is reclosed'at'station- 1. 'However, with the line closed at station 1 and open at station 2, the AE relay will be operated to its spacing position by winding 12 since the opposing current in the line Winding 11 which has been holding the relay in the marking position is now interrupted. The AE relay in the spacing position completes a circuit from battery through its contacts and winding f relay AW to ground to holdthis relay in its marking position. The AE relay also completes the; circuit through the operating wind'ing18 .ofrela'y SE, thus operating this relay. The

SE relay in operating interrupts the locking circuit for the SW' relay from ground through winding 17 of relay SW, operated contacts of the SWV' relay and normal con- .tactsofthe SE relay. This releasesthe SW relay which then completes the locking circuit of the SE relay from ground to winding 19of relay SE, operated contacts of relay SE and normal contacts of the SW relay to bat- .tery. The operation of the SE relay also LE now tends to operate this relay to its" s acing position. Relay 'SVV in releasing a so, transfers condenser 21 from a path in parallel with winding 11 of relay AE to a path in parallel with winding 4 of relay AW and; condenser 22 from winding 13 of relay to winding 6 of relay ATV.

Since the line is still open at; station 2, the LE. relay will'now be operated to itsspacing position. This will interruptthe line circuit' from station 1 so that the associated re stopped at station 1 and station 2 will then send to station 1 through repeater 3 in a manner similar to station 1 sending to station 2.

lVhen station 1 again wishes to transmit, its

line circuit is again interrupted which releasesv the ATV relay. This operates relay SW and releases relay SE and restores the circuit to its original condition. Resistances 146, 1-5; and 20' are used to adjust the biasing current of relays LVV, LE, Al/V and AE to their proper values.

Fig. 2 shows a modification of the'switching arrangementemploying only one relay S, instead of the two relays SlfV and SE. Here, again with station 1 transmitting to station 2, the S relay has been operated by a circuit from ground through winding 24 of this relay and through the spacing contact of the AW relay to battery. The relay then locks operated in a circuit from battery through winding 23 and its operated contacts to ground, connects condenser 29 in parallel with winding 13 of relay AE, and condenser 27 in parallel with winding 11 of the same relay. The biasing current in winding 10 of relay LE tends to hold the relay in the marking position, while that in winding 8 of relay LVV tends to operate therelay to the spacing position, as in Fig. 1 with station 1 transmitting'to station 2.

Then, when the AE relay operates to its spacing position due to station 2 interrupting the line circuit, a circuit is completed from battery through the spacing contact of relay AE, winding 25 of relay S and operated contacts of relay S to ground. The current in this circuit opposes the current in the locking winding 23 so that the relay will release. In releasing it prepares the repeater for repeating signals from station 2 to station 1; by reversing the direction of the biasing current in windings 8 and 10 of relays LlV and LE, respectively transferring condenser 29 from winding 1-3 of relay AE to winding 6 of relay AW and disconnecting condensers 27 from winding 11 of relay AE and connect-ing condenser 28 in parallel with winding 4 of the ATV relay. When station 1 again. wishes to transmit to-station 2, the line circuit at station 1 is interrupted allowing the ATV relay to release when the line is closed at station 2. The release of the A VV relay holds the AE relay operated and operates the S relay as before which restores the circuit to its original position. Resistance 26 is used'to adjust the biasingcurrents to a satisfactory value.

-t should be noted that the S relay contacts associated with winding 23 should break at the same time or slightly before the contacts associatedwith winding 25 breakas-this mans relay is releasing to insure that it will fully release.

Fig. 3 illustratesanother methodof switching condensers 31 and 32 from windings 11 and 13, respectively of relay AE to windings 4 and 6 of relay AW and also the direction theAE relay is operated to its spacing position due to the line circuit at station 2be1ng interrupted, a circuit for advancmg the selector is completed from battery through the spacing contact of theAE relay .andthe are 41 ofthe selector to operate the SEmagnet which will advance the selector. This inturn will. switch the condensers and bias the circuit so that station 2 will be able to send to station 1. The same process is repeated when station 1 again wishes to transmitto station 2. In this case when relay AWV releases, it. again advances the selector and the circuit isreturned to itsgoriginal condition. Resistances33 and I to their proper values.

34 are provided to adjustthebiasing current It should be noted that the pola r relays may be sensitive and fast-operated so that a a high signaling speed may be employed- The f condensers are connected only to the relay subjectjto false operations due to the different rates of current change in its windings.

I Byretarding the action of only this relay, the a other relays may be operated at the1r maxiinum speed and still notbe interierred with Iby false operations of this relay. Also the a switching arrangement permits the d1rect1on of transmission to be automatically changed and still be maintained at the high speed since it applies to retarding condensers to either l tofalse operat1ons and disconnectsthem from of the auxiliary relays which is subjected the relay which must follow the high speed signal impulses.

0 The circuits described comprise one specific embodiment of the invention with several of i the many POSSlblQSWIlZClllDg arrangements to transfer the condensers from one relay to anresults may be obtained with many difierent embodiments and modifications without departing from-the spirit of the invention as defined in the appended claims.

What is claimed: is: 1. A telegraph line repeater comprismg relay means for repeating telegraph signals,

said repeater dependent upon which side of saidrepeater is receiving said signals.

2. A four polar relay repeater for a single line telegraphic system, for repeating signals from one line section of thesystem to another line sec tion,of the type wherein currentfrom.

each linesectioniiscaused to traverse the line windings of twop'olar relaysin series, characterized in this, that electrical retarding" means, comprising condenser apparatus and switching means for automatically connectin'g said apparatus "across the line win 'd ingJofone of said polar relays,are provided 7 for nsur n theproperoperat1on of one or w i more ofsa relaysin predetermined order.

3. A ,repeaterfin accordance with claim 2,

characterized in this, that said switching means j is a relay arrangement adapted to connect the condenser apparatus alternately across one line section or thejother infac'cordance w th which 11116 section is transmitting the s1 nals. i a

*4. repeater in accordance with claim characterized in this, that said switching means is a*rotaryselector arrangement adapted to connect the j condenser apparatus alternately across eachline section in accord ance with whiclrlinesection 'is transmitting thesignals. i

p 5. Means *fonrepeating signals from one transmission line section to another comprising four polar relays constituting means for connecting said sections, biasingiwindings which signals are being received from a line section, and switching means for automatically connecting said retarding means to either of said fourth polar relays dependent upon from which ofsaid line sections the signals originate.

6. A high speed telegraph repeater for repeating telegraph signals from either of two 1ine sections to; the other line section comprismg two sets of polar relays, each having line windings and local circuit windings,

.each of's aid line sections extending through other. It is tobe understood that the same.

the line windings of one set-of relays and a contact-of the otheruset, switching means whereby the currents in the local circuit windings of each set of relays are controlled by contacts of theother set of relays in such a manner that signals repeated from one line section to the other line 1 section are unable to actuate the set of relays associated with said other line section, electrical retarding means to prevent false operation of said relays, and switching means to automatically connect said retarding means to the set of relays associated with theline section to which the sig nals arerepeated.

7 A high speed telegraph repeater for repeating signals received from a telegraph station over a transmissionline to a second telegraph stationovera second transmission line comprising a plurality of polarizedjrelays, electrical retarding meansito insure proper operation of said relays, switching means to connect saidretarding means with 5 the side of the repeater connected to the transmission line associated with the station receiving the signals, and means whereby a break signal transmitted from the receiving station is repeated over theassociated transmission circuit to the sending station.

8. A telegraph repeater for repeating telegraph signals from one telegraph line section to a second line section comprising two polarized line relays and two polarized auxiliary relays each havingi'line' and biasing windings, each of said line sections .eXtending through the line windings of one of the line relays and of the auxiliary relays and thecontacts of the other line relay, the biasing windings of said line relays being connected in series, and switching means for automatically connecting said line relay biasing windings in series with the biasing windings of either ofthe auxiliary relays dependent upon in which of said line sections the signals originate. A r

9. A telegraph repeater in accordance with claim 8 wherein electrical retarding means are provided to prevent false operations of said auxiliary relays, and means for automatically connecting said retarding means to either of said auxiliary relays dependent upon in which of said line sections the signals originate. I

In witness whereof I hereunto subscribe my name this 5th day of February, 1932.

RICHARD B. HEAR-N. 

